On Hybernation, 77 
respiratory organs ceases. He could perceive no motion 
with a microscope, in the flanks of a bat when the ther- 
mometer was at 43°. Sir John Hunter introduced worms 
&c. into the stomachs of lizards, and on examination 
the winter found the food unchanged; “hose that were 
kept until spring voided it unchanged, thus clearly pearing 
the total suspension of the digestive functions. 
n this state all sensation appears to be lost, and one 
function of life alone seems to remain, that 2 cote 
Limbs have been broken, and wounds made i als with 
every appearance of inseasibility. It ag Bede proved 
that a confined circulation is carried on through the heart 
and the larger veins and arteries. 
Mr. Carlisle states “that all ere tee ae ied 
possess a peculiar structure of the heart and its princi- 
pal veins; the superior cava divides into two trunks, the 
left passing over the left auricle of the heart opens into the 
inferior part of the wien auricle.” 
Spallanzani says 
** T have often Genie Newts, Frogs, Toads, and Lizards, 
when torpid from cold, and apparently dead; and | have 
found that the blood did not circulate in the fine: while it 
continued to circulate in the large vessels, although the 
circulation was languid. Il a greater degree 
penetrated the solids, if it has coagulated the blood, then 
it is certain the animals perish.” —Spallanzani, p. 269. > 
hile examining this subject it is necessary for us to 
guard against the similarity of suspended animation and 
hybernation. Spallangani resuscitated animalcule after 
having been ina dry state for 27 years, by adding water to 
them. In this case air was not essenual, nor in hyberna- 
tion do we find it absolutely so. Spallonaani found st 
torpid bats lived seven minutes in an exhauste 
while another bat died in three minutes, In another ex: 
periment a bird and rat did not live one minute in 
ic acid gas, yet a torpid marmot ie gaan hour, and 
deans, of a tee Dipes “oad be. , which was com- 
pletely perevee of the benefit of air ; ys 
“It was discovered enclosed in a ball of olan, about the 
Size. ro a cricket-ball, nearly an inch in thickness, perfectly 
